US2913977A

US2913977A - Press and means for safeguarding same against excessive loads

Info

Publication number: US2913977A
Application number: US592228A
Authority: US
Inventors: Claas Helmut Franz; Claas Reinhold Heinrich; Claas Margarete; Claas Elfriede Margare Therese
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-04-30
Filing date: 1956-04-30
Publication date: 1959-11-24
Anticipated expiration: 1976-11-24

Description

Nov. 24, 1959 H. F. cLAAs ETAL PRESS AND ME 2,913,977 ANS FOR SAFEGUARDING SAME AGAINST ExcEssIvE LoADS Flled April so. 195e 2 Sheets-Sl'uaetl 1 MSB Filed April 30, 1956 NOV. 24, 1959 H, F, CLAAS EI'AL PRESS AND MEANS FOR SAFEGUARDING SAME AGAINST EXCESSIVE LOADS 2 Sheets-Sheet 2 -Mar Armen/Ey United States Patent O PRESS AND MEANS lFOR SAFEGUARDING SAME AGAINST EXCESSIVE LOADS Application'Aplil 30, 1956, Serial No. 592,228

1 Claim. (Cl. 100-50) Our -invention relates to a press and more particularly to a press embodying means for safeguarding the press from damage by an excessive load. Our invention is specially applicable to high pressure baling presses for compressing bulky materials, such as straw.

Prior presses of that kind are frequently liable to be damaged by being subjected to excessive pressures causing some structural elements, such as the driving shaft, gears, container walls or plungers, to be stressed to an extent producing excessive deformations exceeding the elastic limits.

It is an object of our invention to provide a safeguard protecting the presses from damages by such excessive stresses.

It is a further object of the invention to provide a safeguard of simple design which is reliable in operation and may be easily applied to existing presses without requiring basic structural changes thereof.

More particularly, it is an object of our invention to provide a press with a safety device adapted, when the stresses set up in the structural elements of the press exceed a certain limit, to discontinue the actuation of the press by disengaging a cluch or other driving means.

Finally, it is an object Aof our invention to provide a safeguard ofthe character indicated which will not be destroyed under excessive stresses and, therefore, is capable of repeated uses.

Further objects of our invention will appear from the following detailed description of a preferred embodiment, it being understood that the terms and phrases used in describing the invention have been chosen for the purpose of illustrating the same rather than that of restricting or limiting the invention, the features of novelty being pointed vout in the appended claim. In the drawings:

Fig. l is a diagrammatical side elevational view of a high pressure press for baling straw showing the laterally disposed actuating means, partly in section,

Fig. 2 is an end view of the press shown in Fig. 1 viewed from the front with respect to the direction of travel, and

Fig. 3 is a partial perspective illustration showing a stopping mechanism adapted to be actuated by lateral deformation of a gear.

The high pressure straw-baling press 1 is supported by wheels 2 for transportation purposes and is adapted to be towed by a tractor not shown by means of a thill 3, the tractor being of a known type having an output shaft 4 adapted to drive the press-actuating mechanism. The press is provided with a pick-up mechanism 5 adapted to pick up the straw to be baled, such straw being deposited by the pick-up mechanism in a housing trough wherefrom it is fed by a feeder 6 into position in front of a plunger 7 for subsequent compression thereby to bales in a container 8. The plunger 7 is of the oscillating type pivotally suspended by means of plunger arms 36 (only one of the arms being shown in the drawings) and,

Patented Nov. 24, 1959 ICC adapted to be moved by connecting rods 37 (only one of the rods being shown in the drawings) which are pivotally connected to crank pins carried by driving gears 15, 15'. The output shaft 4 of the tractor is operative through the intermediary of a bevel gear transmission 9 to drive a pulley 10 adapted by means of a V-belt 11 to drive the main drive shaft 13.

Spur pinions

14 and 14 are fixed to the main drive shaft 13 and are in mesh with the driving gears 1S, 15 mounted on a shaft 16 journalled in the frame of the apparatus.

When the plunger 7 meets with an excessive resistance causing the shaft 16 to be subjected to an excessive load, such shaft 16 will be flexed causing the gears 15 and to be laterally displaced with respect to a vertical plane in a slanting fashion. A movable member, such as the short arm 17 of a bell crank 24 fulcrumed in a bracket 26 by means of a pivot pin 25 and preferably provided with a roller 18 is mounted close to the lateral face of the gear 15. The bracket 26 is fixed to wall 27 of the frame of the press. Therefore, the lateral face of the gear 15, when laterally displaced in response to excossive stresses imposed on the shaft 16, will engage the roller 18 and will swing the bell crank 24 about the pivot pin 25. The lever 19 of the bell crank is connected by a link 20 to an upright arm Z1 of a short horizontal shaft carrying a downwardly extending short `arm Z2. The latter is connected by a connecting rod 23 with an arm of the housing of the bevel gear transmission 9. The connecting rod 23 is threaded and is adjustably connected with such arm by a pair of nuts. The housing 9 is guided in the frame of the press for vertical adjustment by suitable means not shown.

When the arm 22 is .turned in the direction indicated by the arrow in Fig. 3 in response to the overload condition, it lifts the connecting rod 23, the latter lifting the housing 9 of the bevel gear transmission andthe V-belt pulley 10 journalled therein. As a result, lthe frictional engagement of the V-belt 11 in the grooves of thefpulley 10 will be eliminated, whereby the actuation of the plunger 7 is terminated. The adjustable connection provided between the connecting rod 23 and the housing yof the transmission 9 by means of the nuts permits the pulley 10 to be adjusted for the purpose of controlling the tension of the V-belt. The roller 18 is capableof adjustment relative to the lgear 15 by an adjusting nut 28 provided on the link 20. Moreover, a set screw 29 is provided acting as a stop for limiting the swinging move-` ment of arm 21. a .Y l

The pressure exerted on the plunger 7 by the material to be baled is transferred by means of the connecting rods 37 and the crank pins to the

driving gears

15 and 15 exerting a couple thereon. It is this couple which exes the shaft 16 causing the

gears

15 and 15 to be displaced in a slanting fashion. The lateral displacement of the

gears

15 and 15 will be greatest in the lower dead center position of the crank pins as in this position of the crank pins the plunger will have compressed Vthe straw to a bale and thus will be subjected to the maximum load. For this reason, the arm 17 of the bell crank 24 is preferably provided at the position shown where the couple acting on the

gears

15 and 15 produces the maximum lateral deflection when the plunger is in its flower dead center position.

From the foregoing description it will appear that the roller 18 measures the deformation of the structural element, such as gear 15, of the press and performs a safeguarding operation, such as the lifting of the bevel gear housing 9, in response to the deformation exceeding a predetermined limit. Pulley 10 and the belt 11 constitute, in elect, a safety clutch which may be actuated by vertical displacement of the transmission gear housing 9.

As will appear from the foregoing description, the

press is safeguarded from damage by the provision of safety means which are actuated in response to elastic deformation of the structural elements of the press caused by high stresses to thereby stop the machine and save it from damage. As in high pressure baling presses the deflection of the plunger driving shaft is commensurate with the stresses set up in the press, it is possible to cause such deformation to act on the safety means which stop the press in a purely mechanical manner.

It is well known in the prior art to safeguard machines from damage by overload through the use of slip clutches or belt drives capable of slippage under excessive load or by so-called shear pins. The present invention solves the problem in a novel fashion. As distinguished from shear pins, the novel safety mechanism will not be destroyed under an overload. It does not require any additional clutches. It permits to repeat the safeguarding action as often as desired by the use of reversible means. The invention makes use of the large vertical and horizontal dimensions of the structural elements of baling presses and further makes use of the liberty of relative movement of the structural elements, such movement taking place with a high ration of transmission.

It has been found that when the baling press is subjected to an excessive load, the plunger operating shaft, such as shaft 16 in Fig. 2, will be ilexed causing the gears and 15' mounted thereon to assume a slanting position differing from the normal vertical position. The slanting position of the gear causes the same to wobble during its rotation. The maximum deection occurs at the time when the plunger arrives in the dead center position subjecting the press to the maximum load. Therefore, the roller, such as 18, is disposed in slightly spaced relationship from the outside of the gear 15, mounted on the plunger driving shaft and, therefore, permits the gear in .the normal operation to revolve freely. The roller may be mounted on an arm of a bell crank, such as 24, fulcrumed for pivotal motion about a Xed pivot. The arms of the bell crank are preferably so dimensioned that a sufficiently large stroke will be imparted to the longer arm thereof to stop the operation of the press through the intermediary of another pair of arms, such as 21, 22, fulcrumed on the frame of the press. As soon as the plunger driving shaft is subjected to an abnormal load, the gear, owing to the flexion of the shaft, will assume a position dilering from its normal vertical position and will contact the roller 18, causing the roller to be urged laterally to thereby swing the bell crank.

While in the embodiments described hereinabove the structural element subject to deformation is a gear, such as gear 15, it may be any other suitable element of the press, for instance the plunger 7 or a wall of the container 8 which is likewise subject to elastic deformation.

While the invention has been described in connection with a single embodiment thereof, it will be understood that it is capable of further modifications, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as fall within the scope of the invention or the limits of the appended claim.

What we claim is:

In a press for baling straw and like materials, in cornbination: a plurality of structural elements including a container for receiving the materials and a plunger reciprocable into and out of said container for compressing the materials when advanced into said container, at least one of said structural elements being progressively deformable in response to increasing pressures with which the materials in said container resist the compressing action of said plunger; means drivingly connected with said plunger `for reciprocating same, said means comprising an endless flexible element and a device for driving said flexible'element; and means for bodily moving said device from driving engagement with said eXible element, said last mentioned means comprising an articulatable linkage having a rst end connected with said device and a second end adjacent to said one structural element and displaceable by the latter at least at such times when the deformation of said one structural element attains a given magnitude, said device remaining in driving engagement with said flexible element when the deformation of said one structural element is below said vgiven magnitude and being moved by said rst end out of driving engagement with said flexible element when the second end is displaced by said one structural element and the latters deformation attains said given magnitude, the construction of said linkage being such that the displacements of said second end are transmitted to said rst end at a higher ratio.

References Cited in the file of this patent UNITED STATES PATENTS